Higher elevations like mountain tops usually have more moisture, and fires historically hadn’t burned there very often. But that’s changing rapidly.
The Dixie and Caldor fires in California are the first and second wildfires ever recorded to cross the Sierra Nevada crest and burn down the other side, according to Boise State University researcher Moji Sadegh.
Sadegh said fire managers used to let fires moving up mountain sides burn because they’d eventually reach an area wet enough that they stop progressing.
“But now, they can’t do that because it’s going to reach the top of the mountain, and it’s going to jump the breach and burn on the other side,” said Sadegh, an assistant professor of civil engineering and head of BSU's Hydroclimate Lab.
Sadegh wrote about these changes in a recent article in The Conversation, which is largely based on research he co-authored that showed how large forest fires have increased across high-elevation, mountainous areas since the '80s.
“Across the West, the fires are going up with a median total rate of 252 meters over 1984 to 2017,” he said.
Sadegh said some of these Western forests used to see fires only every hundred years or more, but several landscapes have gone up in flames over the last few years, including in the Cameron Peak and East Troublesome fires in Colorado last year.
Sadegh said we can’t blame a history of fire suppression for this change, though, because fires didn’t have a history of burning there very often. Instead, he says climate change is the driver.
“When we see more and more of these high-elevation fires occur,” he said, “then we can look back and determine that, 'Hey, this was really the warming, because the other factors were absent.'”
He says burn scars across mountain tops could increase avalanche dangers, decrease snowpack and lead to warming waters that could hurt wildlife.
“But that’s not all. Water quality is being impacted by these burn scars. There is a lot of erosion that happens post-fire. There are lots of other contaminants that erode with the soil and come to our reservoirs. And that impacts the treatment necessary for the water before being delivered to cities,” he said.
Sadegh said mountain communities and businesses like ski resorts need to understand the severity of the situation. Fires aren’t behaving the same way anymore, and he said areas with no major fires in recorded history could now be vulnerable.
“Communicating the risk to them is very important. And I want to go back to the city of Paradise. Camp Fire – it killed 85 people.” he said.
Sadegh noted that some of those people didn’t think the risk was too high, and didn’t leave when they still could. They stayed, and they died.
“The fire behavior is so volatile, these recent fires are so destructive, it’s important for all of us to be ready for the new risks that are out there,” he said.
Sadegh encourages people to look at documents available at Firewise USA for tips on how to better protect their homes and communities from wildfire.
This story was produced by the Mountain West News Bureau, a collaboration between Nevada Public Radio, Wyoming Public Media, Boise State Public Radio in Idaho, KUNR in Nevada, the O'Connor Center for the Rocky Mountain West in Montana, KUNC in Colorado, KUNM in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.
